Change the calling convention for BIFs

The current calling convention for BIFs makes it necessary to
handle each arity specially, since each argument for the BIF
also becomes an argument for the C function implementing the BIF,
which makes it hard to allow BIFs with any number of arguments.

Change the calling convention for BIFs, so that BIF arguments are
passed in an array to the C function implementing the BIF.

6 files changed, 64 insertions, 128 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index dd4bf6be07..537a94ce29 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -2209,16 +2209,16 @@ void process_main(void)
 
  OpCase(bif1_fbsd):
     {
-	Eterm (*bf)(Process*, Eterm);
-	Eterm arg;
+	Eterm (*bf)(Process*, Eterm*);
+	Eterm tmp_reg[1];
 	Eterm result;
 
-	GetArg1(2, arg);
+	GetArg1(2, tmp_reg[0]);
 	bf = (BifFunction) Arg(1);
 	c_p->fcalls = FCALLS;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, arg);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2237,17 +2237,17 @@ void process_main(void)
 
  OpCase(bif1_body_bsd):
     {
-	Eterm (*bf)(Process*, Eterm);
+	Eterm (*bf)(Process*, Eterm*);
 
-	Eterm arg;
+	Eterm tmp_reg[1];
 	Eterm result;
 
-	GetArg1(1, arg);
+	GetArg1(1, tmp_reg[0]);
 	bf = (BifFunction) Arg(0);
 	c_p->fcalls = FCALLS;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, arg);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2256,7 +2256,7 @@ void process_main(void)
 	if (is_value(result)) {
 	    StoreBifResult(2, result);
 	}
-	reg[0] = arg;
+	reg[0] = tmp_reg[0];
 	SWAPOUT;
 	I = handle_error(c_p, I, reg, bf);
 	goto post_error_handling;
@@ -2380,14 +2380,15 @@ void process_main(void)
   */
  OpCase(i_bif2_fbd):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm);
+	Eterm tmp_reg[2] = {tmp_arg1, tmp_arg2};
+	Eterm (*bf)(Process*, Eterm*);
 	Eterm result;
 
 	bf = (BifFunction) Arg(1);
 	c_p->fcalls = FCALLS;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, tmp_arg1, tmp_arg2);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2405,13 +2406,14 @@ void process_main(void)
   */
  OpCase(i_bif2_body_bd):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm);
+	Eterm tmp_reg[2] = {tmp_arg1, tmp_arg2};
+	Eterm (*bf)(Process*, Eterm*);
 	Eterm result;
 
 	bf = (BifFunction) Arg(0);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, tmp_arg1, tmp_arg2);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2433,7 +2435,7 @@ void process_main(void)
      */
  OpCase(call_bif0_e):
     {
-	Eterm (*bf)(Process*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 
 	PRE_BIF_SWAPOUT(c_p);
 	c_p->fcalls = FCALLS - 1;
@@ -2442,7 +2444,7 @@ void process_main(void)
 	}
 
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	r(0) = (*bf)(c_p, I);
+	r(0) = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(r(0)));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN_0(c_p, r(0));
@@ -2466,7 +2468,7 @@ void process_main(void)
 
  OpCase(call_bif1_e):
     {
-	Eterm (*bf)(Process*, Eterm, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 	Eterm result;
 	BeamInstr *next;
 
@@ -2477,7 +2479,8 @@ void process_main(void)
 	PreFetch(1, next);
 	PRE_BIF_SWAPOUT(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, r(0), I);
+	reg[0] = r(0);
+	result = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN(c_p, result, reg, 1);
@@ -2501,7 +2504,7 @@ void process_main(void)
 
  OpCase(call_bif2_e):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 	Eterm result;
 	BeamInstr *next;
 
@@ -2514,7 +2517,8 @@ void process_main(void)
 	CHECK_TERM(r(0));
 	CHECK_TERM(x(1));
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, r(0), x(1), I);
+	reg[0] = r(0);
+	result = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN(c_p, result, reg, 2);
@@ -2538,7 +2542,7 @@ void process_main(void)
 
  OpCase(call_bif3_e):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm, Eterm, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 	Eterm result;
 	BeamInstr *next;
 
@@ -2549,7 +2553,8 @@ void process_main(void)
 	}
 	PreFetch(1, next);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, r(0), x(1), x(2), I);
+	reg[0] = r(0);
+	result = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN(c_p, result, reg, 3);
@@ -3326,64 +3331,23 @@ void process_main(void)
 	    ASSERT(bif_nif_arity <= 3);
 	    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
 	    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	    switch (bif_nif_arity) {
-	    case 3:
-		{
-		    Eterm (*bf)(Process*, Eterm, Eterm, Eterm, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, r(0), x(1), x(2), I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		}
-		break;
-	    case 2:
-		{
-		    Eterm (*bf)(Process*, Eterm, Eterm, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, r(0), x(1), I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		}
-		break;
-	    case 1:
-		{
-		    Eterm (*bf)(Process*, Eterm, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, r(0), I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		}
-		break;
-	    case 0:
-		{
-		    Eterm (*bf)(Process*, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		    break;
-		}
-	    default:
-		erl_exit(1, "apply_bif: invalid arity: %u\n",
-			 bif_nif_arity);
+	    reg[0] = r(0);
+	    {
+		Eterm (*bf)(Process*, Eterm*, BeamInstr*) = vbf;
+		ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+		nif_bif_result = (*bf)(c_p, reg, I);
+		ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
+		       is_non_value(nif_bif_result));
+		ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+		PROCESS_MAIN_CHK_LOCKS(c_p);
 	    }
 
 	apply_bif_or_nif_epilogue:
 	    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
 	    ERTS_HOLE_CHECK(c_p);
 	    if (c_p->mbuf) {
-		reg[0] = r(0);
 		nif_bif_result = erts_gc_after_bif_call(c_p, nif_bif_result,
 						  reg, bif_nif_arity);
-		r(0) = reg[0];
 	    }
 	    SWAPIN;  /* There might have been a garbage collection. */
 	    FCALLS = c_p->fcalls;
@@ -3404,7 +3368,6 @@ void process_main(void)
 		}
 		Dispatch();
 	    }
-	    reg[0] = r(0);
 	    I = handle_error(c_p, c_p->cp, reg, vbf);
 	    goto post_error_handling;
 	}
diff --git a/erts/emulator/beam/bif.h b/erts/emulator/beam/bif.h
index 8faa09feb8..cb5d266660 100644
--- a/erts/emulator/beam/bif.h
+++ b/erts/emulator/beam/bif.h
@@ -26,14 +26,14 @@ extern Export* erts_format_cpu_topology_trap;
 
 #define BIF_P A__p
 
-#define BIF_ALIST_0 Process* A__p
-#define BIF_ALIST_1 Process* A__p, Eterm A_1
-#define BIF_ALIST_2 Process* A__p, Eterm A_1, Eterm A_2
-#define BIF_ALIST_3 Process* A__p, Eterm A_1, Eterm A_2, Eterm A_3
-
-#define BIF_ARG_1  A_1
-#define BIF_ARG_2  A_2
-#define BIF_ARG_3  A_3
+#define BIF_ALIST_0 Process* A__p, Eterm* BIF__ARGS
+#define BIF_ALIST_1 Process* A__p, Eterm* BIF__ARGS
+#define BIF_ALIST_2 Process* A__p, Eterm* BIF__ARGS
+#define BIF_ALIST_3 Process* A__p, Eterm* BIF__ARGS
+
+#define BIF_ARG_1  (BIF__ARGS[0])
+#define BIF_ARG_2  (BIF__ARGS[1])
+#define BIF_ARG_3  (BIF__ARGS[2])
 
 #define BUMP_ALL_REDS(p) do {			\
     if (!ERTS_PROC_GET_SAVED_CALLS_BUF((p))) 	\
diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index 9b565b7197..469deb86f0 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -1715,6 +1715,7 @@ Eterm db_prog_match(Process *c_p, Binary *bprog,
     Process *current_scheduled;
     ErtsSchedulerData *esdp;
     Eterm (*bif)(Process*, ...);
+    Eterm bif_args[3];
     int fail_label;
     int atomic_trace;
 #if HALFWORD_HEAP
@@ -1968,7 +1969,7 @@ restart:
 	    break;
 	case matchCall0:
 	    bif = (Eterm (*)(Process*, ...)) *pc++;
-	    t = (*bif)(build_proc);
+	    t = (*bif)(build_proc, bif_args);
 	    if (is_non_value(t)) {
 		if (do_catch)
 		    t = FAIL_TERM;
@@ -1979,7 +1980,7 @@ restart:
 	    break;
 	case matchCall1:
 	    bif = (Eterm (*)(Process*, ...)) *pc++;
-	    t = (*bif)(build_proc, esp[-1]);
+	    t = (*bif)(build_proc, esp-1);
 	    if (is_non_value(t)) {
 		if (do_catch)
 		    t = FAIL_TERM;
@@ -1990,7 +1991,9 @@ restart:
 	    break;
 	case matchCall2:
 	    bif = (Eterm (*)(Process*, ...)) *pc++;
-	    t = (*bif)(build_proc, esp[-1], esp[-2]);
+	    bif_args[0] = esp[-1];
+	    bif_args[1] = esp[-2];
+	    t = (*bif)(build_proc, bif_args);
 	    if (is_non_value(t)) {
 		if (do_catch)
 		    t = FAIL_TERM;
@@ -2002,7 +2005,10 @@ restart:
 	    break;
 	case matchCall3:
 	    bif = (Eterm (*)(Process*, ...)) *pc++;
-	    t = (*bif)(build_proc, esp[-1], esp[-2], esp[-3]);
+	    bif_args[0] = esp[-1];
+	    bif_args[1] = esp[-2];
+	    bif_args[2] = esp[-3];
+	    t = (*bif)(build_proc, bif_args);
 	    if (is_non_value(t)) {
 		if (do_catch)
 		    t = FAIL_TERM;
diff --git a/erts/emulator/beam/erl_trace.c b/erts/emulator/beam/erl_trace.c
index 8833137112..39509f363f 100644
--- a/erts/emulator/beam/erl_trace.c
+++ b/erts/emulator/beam/erl_trace.c
@@ -2092,8 +2092,7 @@ void save_calls(Process *p, Export *e)
  * entries instead of the original BIF functions.
  */
 Eterm
-erts_bif_trace(int bif_index, Process* p, 
-	       Eterm arg1, Eterm arg2, Eterm arg3, BeamInstr *I)
+erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
 {
     Eterm result;
     int meta = !!(erts_bif_trace_flags[bif_index] & BIF_TRACE_AS_META);
@@ -2107,10 +2106,10 @@ erts_bif_trace(int bif_index, Process* p,
 	 * no tracing will occur. Doing the whole else branch will 
 	 * also do nothing, only slower.
 	 */
-	Eterm (*func)(Process*, Eterm, Eterm, Eterm, BeamInstr*) = bif_table[bif_index].f;
-	result = func(p, arg1, arg2, arg3, I);
+	Eterm (*func)(Process*, Eterm*, BeamInstr*) = bif_table[bif_index].f;
+	result = func(p, args, I);
     } else {
-	Eterm (*func)(Process*, Eterm, Eterm, Eterm, BeamInstr*);
+	Eterm (*func)(Process*, Eterm*, BeamInstr*);
 	Export* ep = bif_export[bif_index];
 	Uint32 flags = 0, flags_meta = 0;
 	int global = !!(erts_bif_trace_flags[bif_index] & BIF_TRACE_AS_GLOBAL);
@@ -2122,8 +2121,6 @@ erts_bif_trace(int bif_index, Process* p,
 					       * export entry */
 	BeamInstr *cp = p->cp;
 	
-	Eterm args[3] = {arg1, arg2, arg3};
-	
 	/* 
 	 * Make continuation pointer OK, it is not during direct BIF calls,
 	 * but it is correct during apply of bif.
@@ -2155,7 +2152,7 @@ erts_bif_trace(int bif_index, Process* p,
 	
 	func = bif_table[bif_index].f;
 
-	result = func(p, arg1, arg2, arg3, I);
+	result = func(p, args, I);
 	
 	if (applying && (flags & MATCH_SET_RETURN_TO_TRACE)) {
 	    BeamInstr i_return_trace      = beam_return_trace[0];
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 01dc853184..1005a7b941 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -1647,8 +1647,7 @@ void monitor_generic(Process *p, Eterm type, Eterm spec);
 Uint erts_trace_flag2bit(Eterm flag);
 int erts_trace_flags(Eterm List, 
 		 Uint *pMask, Eterm *pTracer, int *pCpuTimestamp);
-Eterm erts_bif_trace(int bif_index, Process* p, 
-		     Eterm arg1, Eterm arg2, Eterm arg3, BeamInstr *I);
+Eterm erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr *I);
 
 #ifdef ERTS_SMP
 void erts_send_pending_trace_msgs(ErtsSchedulerData *esdp);
diff --git a/erts/emulator/utils/make_tables b/erts/emulator/utils/make_tables
index 918ef62094..91efb4c023 100755
--- a/erts/emulator/utils/make_tables
+++ b/erts/emulator/utils/make_tables
@@ -181,8 +181,7 @@ for ($i = 0; $i < @bif; $i++) {
 print "\n";
 
 for ($i = 0; $i < @bif; $i++) {
-    my $arity = $bif[$i]->[2];
-    my $args = join(', ', 'Process*', ('Eterm') x $arity);
+    my $args = join(', ', 'Process*', 'Eterm*');
     print "Eterm $bif[$i]->[3]($args);\n";
     print "Eterm wrap_$bif[$i]->[3]($args, UWord *I);\n";
 }
@@ -219,28 +218,10 @@ for ($i = 0; $i < @bif; $i++) {
     next if $bif[$i]->[3] eq $bif[$i]->[4]; # Skip unwrapped bifs
     my $arity = $bif[$i]->[2];
     my $func = $bif[$i]->[3];
-    my $arg;
     print "Eterm\n";
-    print "wrap_$func(Process* p";
-    for ($arg = 1; $arg <= $arity; $arg++) {
-	print ", Eterm arg$arg";
-    }
-    print ", UWord *I)\n";
+    print "wrap_$func(Process* p, Eterm* args, UWord* I)\n";
     print "{\n";
-    print "    return erts_bif_trace($i, p";
-    for ($arg = 1; $arg <= 3; $arg++) {
-	if ($arg <= $arity) {
-	    print ", arg$arg";
-	#} elsif ($arg == ($arity + 1)) {
-	  #  # Place I in correct position
-	   # print ", (Eterm) I";
-	} else {
-	    print ", 0";
-	}
-    }
-    # I is always last, as well as in the correct position
-    # Note that "last" and "correct position" may be the same...
-    print ", I);\n";
+    print "    return erts_bif_trace($i, p, args, I);\n";
     print "}\n\n";
 }
 
@@ -261,19 +242,9 @@ for ($i = 0; $i < @bif; $i++) {
     my $orig_func = $1;
     $orig_func = $implementation[$i] if $implementation[$i];
     print "Eterm\n";
-    print "$func(Process* p";
-    for ($arg = 1; $arg <= $arity; $arg++) {
-	print ", Eterm arg$arg";
-    }
-    print ")\n";
+    print "$func(Process* p, Eterm* BIF__ARGS)\n";
     print "{\n";
-    print "    return $orig_func(p";
-    for ($arg = 1; $arg <= 3; $arg++) {
-	if ($arg <= $arity) {
-	    print ", arg$arg";
-        }
-    }
-    print ");\n";
+    print "    return $orig_func(p, BIF__ARGS);\n";
     print "}\n\n";
 }